“…gather the hundred most brilliant minds in the world together in a room… and ‘have them ask each other the questions they were asking themselves’.”

John Brockman, editor of Edge.org, inserted the technology of the Internet into this intriguing plan and now asks contributors to each anniversary edition to respond to a question “that comes to me, or to one of my correspondents, in the middle of the night.” A particularly tricky question was presented to scientists from a variety of disciplines in 2008 – what have you changed your mind about?

Most of us are familiar with the bumper sticker that reads I’ve made up my mind – don’t confuse me with the facts. It’s a malady to which we all fall victim, and the wealth of misinformation spread through viral emails has certainly exacerbated the syndrome. The average person, having chosen an opinion based on the first headline that conforms to his or her personal beliefs, steadfastly refuses to seek out or accept any contradictory information. If admitting that we’re wrong is so difficult for the average mind, it must be far more challenging for the genius-level scientists who spend their days examining, researching, and formulating well-thought-out theories.

Nevertheless, contributors to What Have You Changed Your Mind About? attack the subject with surprising candor and humility. In more than a hundred succinct essays, we’re allowed the privilege of glimpsing the thought process involved when some of the world’s most respected minds rethink their ideas. Sometimes the turnabout is the result of new information, sometimes it is the aha! experience that comes from seeing the same old information in a new light. Some of the authors appearing here simply grew into new theories as a result of age and experience.

The topics of essays in this book are as diverse as the authors. Psychologist and computer scientist Roger Schank contemplates the possibility that machines may not have the ability to emulate human intelligence after all. Meanwhile computer scientist Rudy Rucker has come to believe “that we can in fact create humanlike computer programs.”

Susan Blackmore, who “trained as a witch, attended spiritualist churches,” and ruined any hope of being taken seriously by academia confesses that she had to change her mind about the existence of paranormal phenomena. And philosopher Mick Bostrom covers all bases with his sensibly simple statement “Since I started my life knowing virtually nothing, I have changed my mind about virtually everything.”

From Martin Rees, Freeman Dyson, Ray Kurzwiel, Alan Alda, and dozens of others come surprising confessions of those change-of-heart moments that are so difficult to accept. There is no need for the reader to agree with any of the opinions. After all, as Randolph Hess points out,

“I used to believe that you could find out what is true by finding the smartest people and finding out what they think. However, the most brilliant people keep turning out to be wrong.”

What Have You Changed Your Mind About? is not a book of answers but rather a book of ideas. Each contributor explains the reasoning behind both sides of the opinion. It’s a fascinating opportunity to view the way scientifically trained minds assess and then reassess the significance of facts.

For readers who remain open and dispassionate, What Have You Changed Your Mind About? may be a motivational tool, encouraging us to explore our own erroneous and outdated notions. As PZ Myers reminds us, “That flexibility is intrinsic to being human…” Changing our minds is not flip-flopping but the only intelligent way to proceed as we gain experience and knowledge.